Hellström P A
Hearing Research Lab., Gothenburg, Sweden.
J Acoust Soc Am. 1993 Sep;94(3 Pt 1):1301-6. doi: 10.1121/1.408157.
Three groups of 12 subjects were utilized for an experiment in which the temporary threshold shift due to a free-field exposure was measured and compared to the sound transfer functions from free-sound field to the subjects' eardrums. Subject selection was based upon their sound transfer functions and the requirement of normal hearing. The subjects were assigned to one of three groups depending on their dominantly sound transfer function frequency: Low, middle, or high. A probe tube with a miniature microphone was used for the measurement of the sound transfer functions in 1/3-oct bands. The measurements were performed in frequency bands from 0.2 to 20 kHz with one direction of sound incidence: 0 degree azimuth and 0 degree elevation. The subjects were exposed twice to a 2-kHz and twice to a 4-kHz narrow-band noise monotonically on four different occasions. Pre- and postexposure sweep Békésy audiograms were recorded and the temporary threshold shift calculated as the difference between the two. The averaged temporary threshold shifts differed significantly among groups.
三组，每组12名受试者参与了一项实验，实验测量了自由场暴露导致的暂时阈移，并将其与从自由声场到受试者耳膜的声传递函数进行了比较。受试者的选择基于他们的声传递函数以及正常听力的要求。根据其占主导地位的声传递函数频率，受试者被分配到三组中的一组：低、中或高。使用带有微型麦克风的探头管测量1/3倍频程频段的声传递函数。测量在0.2至20 kHz的频段内进行，声入射方向为：0度方位角和0度仰角。受试者在四个不同场合分别两次暴露于2 kHz和两次暴露于4 kHz的窄带噪声中。记录暴露前后的扫频贝凯西听力图，并将暂时阈移计算为两者之间的差值。各组的平均暂时阈移差异显著。
